Implosion panel spacing device



Aug. 1952 A. D. GIACCHETTI ETAI. 3,05L782 IMPLOSION PANEL SPACING DEVICEFiled July 13, 1959 INVENTORS Unite Filed July 13, 1959, Ser. No.826,698

9 Claims. (Cl. 17s 7.s2

This invention relates to improvements in television picture tubeswherein the face of the picture tube is confronted by an implosion panelcongruent therewith.

It will be understood that, heretofore, it has been the practice toemploy a flat pane of sufficiently strong glass before the face of thepicture tube in order to protect the observer from fiying fragments inthe event of implosion. More recently, and in order to reduce the frontto back dimension of the cabinet which houses the chassis, including thepicture tube, there has been introduced a concave implosion panelarranged to nest with the convex face of the picture tube except for theinterposition of a thin layer of transparent plastic composition, aswill appear. By means of thi expedient the implosion panel may protrudebeyond the front face of the cabinet which latter may be foreshortenedcorrespondingly.

Inasmuch as the implosion panel is curved congruently with the tube faceand is spaced therefrom by a thin layer of some suitable, transparentplastic, e.g. an epoxy resin, it is important that such spacing bemaintained uniform over the coextensive areas of the panel and tube forotherwise errors of refraction give rise to undesirable distortion ofthe raster. Moreover, it has been found that if the thickness of theresin layer varies from point to point cracking thereof occurs. Thepresent invention has for its principal object the provision of aspacing member particularly adapted to determine the necessary spacingbetween the panel and tube and to maintain such spacing.

A further object is to provide a spacing member as aforesaid whichcooperates with the ears ordinarily forming part of the implosion paneland located at the four corners thereof.

Other objects are to provide a spacing member as aforesaid which isfoolproof in installation, reliable during the life of the assembly ofwhich it forms a part, is inexpensive and adaptable to variations in thecurvature of the juxtaposed surfaces.

An additional object is to provide a spacing member as aforesaid whichwill not interfere with introduction of the fluid resin to theinterspace.

In an alternative aspect We provide a combined spacing member and shoeadapted to fit over the ears of the panel to act as a cushion forclamping means by which the front end of the tube and the panel may besecured in position with respect to the front panel of the cabinet.

, Other objects and advantages will appear from the ensuing descriptionwhich, taken with the accompanying drawing, discloses certain formswhich the invention may be embodied in practice.

In this drawing:

FIG. 1 is a front elevational viewof the tube and implosion panelshowing three of the invention devices in place, the remaining one beingomitted for convenience of illustration;

FIG. 2 is a cross section taken on the line 2-2 of FIG. .1, but somewhatmagnified;

3,5l,72 Patented Aug. 28, 1962 FIG. 3 is a detail in perspective of apreferred form of the invention;

FIG. 4 is a detail in perspective of a modified form of the device;

FIG. 5 is a cross section similar to FIG. 2, but showing the device ofFIG. 4; and

FIG. 6 is a detail in perspective of still another modification.

Regarded broadly, the invention device comprises a spacing member ofresilient material including a portion to embrace an ear of theimplosion panel with which the device is assembled. In this connectionit will be understood th-at the invention contemplates a form ofimplosion panel of substantially rectangular form having alaterally-extending car at each corner which, as a group, are designedto cooperate with clamps to fix the panel and tube in predeterminedrelation relative to the opening in the front panel of the cabinetthrough which the tube and panel protrude. The invention devicetherefore comprises a portion to be positioned over the ear forretention of the same in a defined spacing position together with a tabor tabs which extend between the confronting faces of the panel andtube. From the standpoint of economy of manufacture and assembly aonepiece device is preferred. Moreover, to obtain the desired pliabilityand shock-absorptive character the device is preferably of plasticcomposition, e.g. medium or high density polyethylene or nylon. However,rubber, both natural and artificial, fiber, hard felt or equivalentmaterials may be used. The tabs need only be long enough to provide thespacing since to make them too long may produce areas of interferencewith the raster. Inasmuch as the face of the tube is customarily roundedat its margins where it merges with the substantially frustopyramidalbody of the tube the implosion panel is similarly curved. Accordingly,by employing flexible tabs the same may accommodate to such curvature.Obviously, in the event a relatively rigid tab is provided it may bepre-curved correspondingly. In the alternative aspect the portion of thedevice which fits over the ear is a cap or collar covering at leastthose surfaces of the car which receive clamping pressure and thespacing means are tabs extending therefrom.

Turning now to the drawing we have shown a television picture tube ofconventional form having a front, convex face 10 of substantiallyrectangular contour to which is apposed an implosion panel 11 ofcorresponding contour which is returned about its periphery, as a skirt12, congruently with the rounded forward corners or margins of thepicture tube. At its four corners the panel is provided with integralears 15 of generally parallelepipedic configuration against which clampsmay be secured whereby the panel and tube are secured to the rear of thefront panel 20 of the cabinet.

In order to obtain a listing of the combined tube and implosion panelwith the Underwriters Laboratories, it is necessary to space the samesome predetermined distance apart and to fill the space by flowing in aplastic composition 30 of refractive index equal to that of the glass.Thus, when the composition has solidified it serves to space permanentlythe two surfaces between which it is applied and, to the necessaryextent, to cement the panel to the tube. Certain epoxy resins are foundcompletely suitable for the foregoing purpose.

However, maintenance of the spacing of the two surspaced relation withthe panel.

faces from the time the resin is poured therebetween, and

'has hardened presents a problem. Obviously spacers cannot be introducedinto the viewing area. Our invention meets this requirement byinterposing spacing elements at the more or less common margin of thetube face and panel and maintaining these elements accurately andreliably during such time as the resin is introduced and hardened. Itwill be understood that, during this process, the panel is laidhorizontally on a proper support and the tube is positioned with itsaxis vertical and in necessary To this end we provide members 17, asbest seen in FIG. 3 each of which comprises a strap portion 17 includinga transverse element 17a and legs 17b defining an opening 18 to receivean associated car 15 whereby the member 17 is retained both laterallyand in a fore-and-aft sense. The legs 17b continue adjacent the ear '15to terminate in tabs 19 which may be comparatively rigid and conformedto the surfacesto be separated or flexible to be conformed =byjuxtaposition of the tube and panel. In either case the thickness of thetabs will be such as to produce the desired spacing for reception of theresin lamina. It will be apparent that the device remains in placepermanently due to the cementing action of the plastic in which the tabsare embedded, and that the tabs 19 are of a length calculated not topresent opaque areas on the raster. Alternatively the tabs 19 may be asingle tab centrally of the device.

In the event the implosion panel is not provided with the ears 15 thedevice may be received over the skirt of the implosion panel by a simplehooking engagement, without alteration in the basic configurationdisclosed.

In the modification of FIG. 4 the ear-engaging portion is a rectangularcap 21 received snugly over the ear 15.

In this case a resilient material is more or less obligatory as thedevice is intended to act as a cushion to absorb pressure of clampsapplied to the ears and for absorbing shock and vibration which mightotherwise fracture the .glass. Thetabs 19a correspond in constructionand function with the tabs 19 of FIG. 3.

As a further alternative FIGS. 5 and 6 illustrate a device in which theear-engaging portion 23 is a collar pass- .ing snugly around the carfunctioning similarly to the portion 21 of FIGS. 4 and 5. It will beevident that the tabs 1% function as before. It will be noted that, inthe embodiments of FIGS. 4 and 6, the ear-engaging portion of thedevice, if made of polyethylene or other elastic material, may bedimensioned to grip the ear whereby inadvertent dislodgment, as mayoccur during the process of uniting the tube and panel, is obviated.

Having in mind that the somewhat shorter radii of curvature of themarginal portions of the tube face and panel respectively (regarded-in atransverse aspect) are considerably less than the radii of the principalsurfaces of the same, and, in order to accommodate the spacing tabs moreideally to these homologous marginal surfaces, the principallongitudinal axes of the pair of tabs 19, 19a or 19b are converged to apoint which is approximately the pole of the corners of the margins(regarded as an octant of a spherical surface).

While we have shown particular embodiments of our invention, it will beunderstood, of course, that 'we do not wish to be limited thereto sincemany modifications may be made and we, therefore, contemplate by'theappended claims to cover any such modifications as fall within the truespirit and scope of our invention.

;We claim:

1. In combination a cathode ray tube having a front viewing face, animplosion panel substantially coextensive with said face, confrontingthe same and having a predetermined spacing therefrom, said panel beingprovided with a peripheral flange, and a plurality of devices, eachdevice comprising a portion engaging said flange and a spacing tabextending from said portion interposed between the confronting faces ofthe tube and panel, said tab being sandwiched between said confrontingfaces to maintain said predetermined spacing, and means precludingrelative displacement between said tube and panel.

2. In combination a cathode ray tube having a front viewing face, animplosion panel substantially coextensive with said face, confrontingthe same and having a predetermined spacing therefrom, said panel beingprovided with a plurality of spaced apart ears extending from theperiphery thereof, and a plurality of devices one individual to eachear, each device comprising a portion engaging its associated ear and aspacing tab extending from said portion interposed between theconfronting faces of the tube and panel, said tab being sandwichedbetween said confronting faces to maintain said predetermined spacing,and means precluding relative displacement between said tube and panel.

3. The combination in accordance with claim 2 in which each said car hasa forward face substantially parallel to the principal plane of thepanel and opposite end faces, said ear-engaging portion is a strappassing around said forward face and the opposite end faces, and saidtab forms a continuation of an end of the strap.

4. The combination in accordance with claim 2 wherein said ear-engagingportion and tab are integral.

5. In combination a cathode ray tube having a front viewing face, animplosion panel substantially coextensive with said face, confrontingthe same, and having a predetermined spacing therefrom, said panel beingprovided with a plurality of substantially parallelepipedic earsextending laterally from the periphery thereof, each said ear includinga forward, principal face parallel to the principal plane of the paneland opposite end faces, and a plurality of devices one individual toeach ear, each device comprising a portion overlying said forward faceof its associated ear and a tab extending from each end of saidoverlying portion sandwiched between said confronting faces to maintainsaid predetermined spacing, and means precluding relative displacementof said tube and panel.

6. The combination in accordance with claim 5 further characterized bythe provision of an extension at each end of said overlying portionadjacent said opposite end faces of the ear and each said tab is acontinuation of a said extension. 7

7. In combination a cathode ray tube having a front viewing face, animplosion panel substantially coextensive with said face, confrontingthe same and having a predetermined spacing therefrom, said panel beingprovided with a plurality of substantially parallelepipedic earsextending laterally from the periphery thereof, a plurality of devicesone individual to each ear, each de- .vice comprising a cap-shapedmember embracing its associated ear to prevent dislodgment of the devicetherefrom, and 'a spacing tab extending from said member interposedbetween said confronting faces to maintain said predetermined spacing,and means precluding relative displacement between said tube and panel.

8. In combination a cathode ray tube having a front viewing face, animplosion panel substantially coextensive with said face, confrontingthe same and having a predetermined spacing therefrom, said panel beingprovided with a plurality of substantially parallelepipedic earsextending laterally from the periphery thereof, a plurality of devicesone individual to each ear, each said device comprising a collarembracing the ear and a tab extending from said collar interposedbetween said confronting faces to maintain said predetermined spacing,and means precluding relative displacement between said tube and panel.

9 In combination a cathode ray tube having a front viewing face, animplosion panel substantially coextensive with said face, confrontingthe same and having a predetermined spacing therefrom, said tube faceand panel at least in the marginal confronting areas of their respectivefaces being homologously convex and concave respectively, said panelhaving a plurality of ears extending lat- References Cited in the fileof this patent erally fro n the periphery thereof, a plurality 9fdevices UNITED STATES PATENTS one individual to each ear, each devicecomprising a portion engaging an associated ear and a spacing tabextend- 1,912,847 Klein} June 6, 1933 ing from said ear-engaging poitioninterposed between 5 2,091,152 MalPlca 1937 Said marginal areas tomaintain said predetermined spac- 2497660 Dsvme 14, 1950 ing, said tabbein-g curved congruently with the homolo- 2,525,921 Madam 1950 gouscurvature of said areas, and means precluding rela- 216540880Elsenkramer 1953 2,716,231 Blayney Aug. 23, 1955 tive displacementbetween said tube and panel.

